1. Field of the Invention
The present invention relates generally to a centrifugal impeller, and more specifically to a centrifugal impeller for a rocket engine.
2. Description of the Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
Centrifugal impellers are used in rocket engines to deliver high pressure fluid to a main combustion chamber. The centrifugal impeller includes an axial inlet and a radial outlet. The prior art centrifugal impeller has a single radial outlet that is at the highest pressure that the impeller can produce. Some of the radial outlet fluid is bled off and used in other parts of the engine. However, this bleed off fluid is at the higher pressure and must be lowered in pressure for use in other parts. This results in a waste of energy since the work to increase the fluid pressure used in the bleed off fluid is not used in the engine. In a rocket engine, the work performed on the fluid to produce the high pressure also increases the fluid temperature and thus the amount of power needed from the turbine. The extra power needed usually results in increased turbine temperature. The increased power required to pump the fluid to the higher pressure will increase the turbine temperature.